COLUMBUS, Ohio -- The stress that many breast cancer patients
experience as a result of their diagnosis and treatment may lead to a weakened
immune system, a new study suggests.

Researchers at Ohio State University found that patients who reported
high levels of personal stress scored lower than less-stressed women on
three measures of immune function.

The results were surprisingly strong, and clearly suggested an association
between high stress and lower levels of immunity in breast cancer patients,
said Barbara Andersen, leader of the research team and professor of psychology
and obstetrics and gynecology at Ohio State University.

Andersen, who is also a member of Ohio States Institute for Behavioral
Medicine Research and Comprehensive Cancer Center, reported the teams results
February 14 in Seattle at the annual meeting of the American Association
for the Advancement of Science.

She conducted the study with Ronald Glaser, professor of

medical microbiology and immunology, and William Farrar, associate professor
of surgery, both at Ohio State.

The ongoing study has so far included 115 women with Stage II or Stage
III breast cancer being treated at the Arthur G. James Cancer Hospital and
Research Institute at Ohio State or by collaborating physicians in the Columbus
area.

The women entered the study after surgical treatment and before they
began any additional therapy. The women completed questionnaires that examined
signs of stress such as intrusive thoughts about the disease and attempts
to avoid thinking or talking about it.

The researchers then tested the women for three signs of immune function.
One test was the ability of the bodys natural killer (NK) cells to find
and kill target cells.

Natural killer cells have an extremely important function with regard
to cancer because they are capable of detecting and killing cancer cells,
Andersen said.

We found that high levels of stress did not reduce the number of NK
cells, but stress seemed to make the NK cells less effective.

Patients were also tested to see how they reacted to gamma interferon,
a protein that stimulates the NK cells to do their job. The third immune
system test was to determine how well blood cells replicate in the presence
of two plant chemicals -- ConA and PHA. In these two tests as well, highly
stressed women showed evidence of weakened immune response.

These results held up even after the researchers took into account other
factors that can influence immunity in breast cancer patients, including
the patients ages, disease severity and the days since surgery.

Even after you control for these health variables, stress remains a
significant predictor of immune function, Andersen said.

The results are consistent with studies by Glaser and others that have
found links between stress and immune function in relatively healthy individuals.
Were showing that the same relationship between stress and immune function
occurs in people with cancer, Andersen said.

The researchers are beginning to look at whether psychological interventions
to reduce stress in breast cancer patients can also improve immune function.

Psychological interventions may play an important role, not just in
improving quality of life, but also improving the health of breast cancer
patients, Andersen said. Thats what were exploring now.